1. Field of the Invention
The present invention pertains to an electronic blackboard system suited to the production of hard-copy of pieces of information written on an information writing board such as a white board or a blackboard.
2. Description of the Prior Art
FIG. 1 is a front view showing a conventional electronic blackboard system. FIG. 2 is a side view of the electronic blackboard system illustrated in FIG. 1. FIG. 3 is a block diagram showing a flow of signals in the electronic blackboard system of FIG. 1. In the figures, the reference numeral 1 stands from an information writing board; the numeral 2 denotes a guide rail laid horizontally on the upper edge of the information writing board 1; 3 represents a photoelectric conversion device having its one end supported on the guide rail 2 in such a manner that a photoelectric device is movable from side to side, this photoelectric device including a longitudinally formed CCD (Charge Coupled Device) image sensor, a light receiving part disposed in front of this sensor and light emission diodes (LEDs) arranged in a line on the sides of the light receiving part; 4 designates a driving unit, fitted to both ends of the photoelectric device 3, for moving the photoelectric device 3 leftwardly and rightwardly in synchronism with each other; 5 denotes a positional detector consisting of a LED and a photosensor which stand face to face with respect to each other, this positional detector serving to detect the fact that tongue pieces 2a provided at both ends of the guide rail 2 are interposed between the LED and the photosensor; 6 designates a signal cable connected to a power source (not illustrated); 7 stands for a buffer memory for storing image information sent from the photoelectric device 3; 8 denotes a hard-copy device such as a printer or the like; and 9 represents a stand equipped with a vertical frame 9a and a guide rail 9b the vertical frame serving as a supporter for the guide rail 2, the buffer memory 7 and the hard-copy device 8 and the guide rail part 9b supporting the lower end of the driving unit 4, this stand stably supporting the entire system on the floor.
Next, the operation of the conventional electronic blackboard system illustrated in FIG. 1 will be described. In the electronic blackboard system constructed in the above-described manner, the photoelectric device 3 to be employed is of a so-called closely contactual type where the light receiving part and the LEDs are spaced slightly away from an information input face. This device 3 serves to read the information written on the information writing board 1 along the longitudinal lines and convert the thus read information into electrical signals. The photoelectric device 3 is transferred leftwardly or rightwardly at a given velocity by means of the driving unit 4 and is then halted at a position in which the positional detector 5 detects the presence of the tongue pieces 2a, i.e., this device 3 stops at the left or right end of the information writing board 1. In this way, when the photoelectric device 3 is transferred from the left end of the information writing board 1 to the right end thereof and vice versa, the image information equivalent to one picture is obtained from the CCD image sensor which constitutes the photoelectric device 3. Subsequent to the storage of the image information in the buffer memory 7, the image information is recorded by the hard-copy device 8.
The conventional electronic blackboard system is thus constructed, and hence the information writing board 1 and the stand 9 are so disposed as to be constitutively (or essentially) associated with other components like the guide rail 2, the driving unit 4 and so on. The conventional electric blackoard system is prepared for exclusive use and is incapable of enabling read-out from an existing white board or blackboard mounted on a wall.